17-Ketosteroids urine

Overall, other adrenal androgens also show a progressive decrease in urinary excretion in both men and women. Thus, the mean 17-ketosteroid urine levels of elderly people are about 50% of those in young adults. This is primarily secondary to decreased dehydroepiandrosterone (DHEA) and androsterone production. In men, about one-third of the daily 17-ketosteroids are of testicular origen, the remainder being mainly from the adrenals. Androstenedione is a prehormone for testosterone. 

A. Molecular Ion Because of low volatility, most steriods are derivatized before analysis by GC/MS. Molecular ions are usually observed for steriods sufficiently volatile to be analyzed underivatized by GC/MS (see Figure 31.1) Some important steroids in urine include estrone, estradiol, estriol, pregnanediol, and 17-ketosteroids. which can be analyzed by GC/MS as the TMS or the MO-TMS derivatives. The plant steroids, such as camposterol, ergosterol. stigmasterol, cholestanol, and sitosterol, are generally analyzed as the TMS derivatives. 

A -3-Ketosteroids, e.g. testosterone and epi-testosterone in urine I80°C, 20 min Pale blue induced fluorescence (Xfl = 440 nm) for A -3-ketosteroids, detection limit 5 ng. 

The determination of 17-ketosteroids is most often determined in the clinical laboratory by the Zimmerman reaction, in which the ether-extracted material is allowed to react with m-nitroaniline to yield a colored product. Thus, any compound with the 17-keto basic structure such as reserpine, morphine, ascorbic acid, or their metabolites will interfere. The Porter-Silber reaction used in the determination of 17,21-dihydroxysteroids is also not specific, and the reaction requires a di-hydroxyacetone side chain. Paraldehyde, chloral hydrate, meprobromate, and potassium iodide have been found to interfere, and patients should be maintained free of these drugs for 24-48 hours before the urine collection (Bll). 

The following procedure was developed for urinary pregnanediol, pregnanetriol, and 17-ketosteroids in urine. It is similar to the one presented earlier for pregnanediol (12). Hydrolysis is complete because sulfatase for the cleavage of sulfates is included with the B-glucuronidase. 

The same modified reagent has also been used with effect in the analysis of terpenoids and other steroids, and especially for the anabolic steroids. These applications are mentioned only as a passing reference because, like cholesterol, the analytes are more readily determined using zero and/or first order derivative spectrophotometry. If there is one distinct advantage associated with CD detection it is that the 17-ketosteroids, which are major interferences to absorbance detection in the analysis of urine for anabolic steroids, do react with the loss of all CD activity. 

The possibility of preliminary isolation of substances under analysis in the form of hydrazones is frequently utilized in the determination of ketosteroids in complex mixtures such as biological materials. In this form they are even sometimes subjected directly to GC analysis. Charransol et al. [378] determined androstanediol and testosterone in urine. After hydrolysis the sample was extracted with methylene chloride, evaporated and treated with Girard T reagent. Free hydroxysteroids were extracted with diethyl ether and... 

Dihydroxy-20-Ketosteroids, Determination in Urine and Plasma (Silber... 

Urine, Determination of 17,21-Dihydroxy-2-Ketosteroids in (Silber and Porter). 4 139... 

Urine concentrations of C17-ketosteroids (but not of C17-hydroxysteroids) can be falsely raised by nalidixic acid (34). 

High-dosage penicillin produces abnormally high concentrations of 17-ketogenic steroids in the blood and high concentrations of 17-ketosteroid in the urine (257). 

The main excretory metabohtes of androstenedione, testosterone, and DHEA are shown in Figure 53-5. Except for epitestosterone, these catabolites constitute a group of steroids known as 17-ketosteroids (17-KSs). These metabolites are excreted primarily in the urine (>90%), with approximately half as 17-KSs, and half as diols, triols, conjugates, and other polar compounds." ... 

Some estimates of the precision of various typical modem procedures are given in Table 3. General clinical chemists may well be surprised at some of the values when compared with objective experience in other areas. Thus it is well known that the estimation of serum bilimbin has a coefficient of variation (C.V.) of around 15% in most laboratories, and that with creatinine a value of 8-10% is fairly normal (W3). In a recent blind (but not double-blind) interlaboratory trial of a standardized method for 17-ketogenic steroids and one for 17-ketosteroids, Gray et al. (GIO) obtained C.V. s varying between 4% and 14% for both methods. Six of the ten laboratories cooperating in the trial had special steroid experience and were asked to obtain duplicate estimates of any thirty routine specimens of urine. These results are for two well-established and relatively simple procedures. 

Ketosteroids (U) GLC (paper LLC) Comparison with established method, part of procedure (open) Replicates of urine samples or pools (double-blind) 3% to 12% L9, p. 1... 

Darcey and Evenson (D4) have compared GLC and the Zimmerman reaction in the analysis of total 17-ketosteroids in urine. Urinary 17-keto-steroid GLC patterns have been studied by Cawley et al. (C5), who noted the presence of several peaks with retention times shorter than those of 17-ketosteroids. A comparison of different methods of hydrolysis has been made by Curtius and Muller (C18) in their study of the GLC of 17-ketosteroids and progesterone metabolites of urine. The simultaneous determination by GLC of pregnanediol and pregnanolone in urinary extracts has been reported by Guarnieri and Barry (G8). GLC was found to be the method of choice in a study by Barry et al. (B2) of four methods for the quantitative analysis of pregnanediol in urine. 

C18. Curtius, H. C., and Miiller, M., Gas-liquid chromatography of 17-ketosteroids and progesterone metabolites of urine Comparison of different methods of hydrolysis. J. Chromaiog. 30, 410 27 (1967). 

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